Peak Day vs High

So I have been very diligently using the Clearblue Digital OPK. We had intercourse on the high fertility day before peak and the day after peak, but because of circumstance missed the actual peak day. What are the chances of getting pregnant? I drive myself crazy month after month. I have an awesome 17 month year old but anxious for another one. I want them to be close in age and that is getting further and further away. With my daughter I had an <a href="">IUI</a> after unexplained fertility for a year. Will we be able to conceive on our own?